As Snap Inc. files for its IPO, here’s what grown-ups need to know about the social network millennials love so much.

The following sign should appear as you enter the Snapchat app: You must be 25 or younger to ride. Figuring out the interface may pose a risk to people who remember VCRs and Walkmans.

Snapchat can make you feel old. But as Snap Inc. filed its plans for an initial public stock offering that could value it at $25 billion or more, it’s time for us grown-ups to stop shooing this millennial enigma off our lawns.

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